Mene ne mesodam, da kuma abin da yake ta ci gaba?

Embryogenesis - wani hadadden tsari, wanda aka halin sauka a hankali samuwar gabobin da kyallen takarda. Mai kwayar kwayoyin, da jam amfrayo kunshi uku yadudduka: ectoderm, da indodem, mesodam. Mene ne mesodam? Kuma chitin kwarangwal na arthropod da epidermis na fata, da kuma juyayi tsarin ne na ectodermal asalin. Narkewa kamar, endocrine da numfashi tsarin kafa daga indodem. To, ta yaya gabobin da kyallen takarda bada Yunƙurin zuwa mesodam? Kamar yadda aka kafa?

Mene ne mesodam. definition

Wani nama, ko Gabar tsarin kafa na wani Layer amfrayo Kwayoyin. Mene ne mesodam? A ilmin halitta, da definition shi ne cewa shi ne daya daga cikin jam yadudduka, daga abin da a lokacin embryogenesis kafa yawan gabobin da kyallen takarda. Na biyu sunan mesodam - mezoblast. Da samuwar wannan Layer ne hankula ga mafi kwayar dabbobi (togiya: da irin zane da kuma irin Coelenterates).

Mesodam dake tsakanin ectoderm da indodem. Kowace daga cikin makwabtaka da jam yadudduka iya shiga a cikin samuwar mezoblasta. Haka kuma, iri biyu asalin asirce tsakãtsaki ce tayi Layer: entomesoderm, ekzomezoderma. Akwai kuma yanayi inda samuwar mezoblasta shiga sau biyu Tsarin.

Mesodam a matsayin mai raba nucleation takardar kafa a mataki gastrulation.

Mesodam samuwar. Features na samuwar

Mene ne mesodam? A ilmin halitta, shi ne a zaci cewa kowane sashen wata kwayar dabba embryogenesis kafa daya daga cikin jam yadudduka. Samuwar mesodam - hankula aramorfoz irin flatworms .. Saboda haka to sun kafa na farko gaskiya tsakiya germinal Layer. Rubuta Sponges da kuma irin Coelenterates ne wakilin bilayer dabbobi a embryogenesis kafa kawai ectoderm da indodem.

Ta yaya ne da samuwar da mesodam?

Akwai hanyoyi uku na ilimi mezoblasta.

1. Teloblastichesky. Protostomes halayyar dabbobi. Kowane cell an kafa daga mesodam teloblastov wanda karya tsakanin ecto- da indodem. A sakamakon biyu tube tare da mesodam jam tayi.
2. Enterocoel. Wannan hanya na samuwar da mesodam ne hankula ga mafi deuterostome (kruglorotnye, kifi, halittar dabba mai kafafuwa). Mesodam Kwayoyin suna kafa daga raba sassan na m Gut.
3. Daga cikin ectoderm. Irin wannan hanyar an samu a cikin dabbobi masu rarrafe, da tsuntsaye da kuma dabbobi masu shayarwa. Its peculiarity ne cewa mesodam aka kafa ta invagination na ectoderm.

A tsarin da mesodam

Mene ne mesodam? Wannan ba kawai wani tari na m Kwayoyin, kuma bambanta cikin da dama aikin sassan na iri Layer. Rabuwa mezoblasta auku a hankali, sakamakon wadannan yankunan suna kasaftawa:

1. Somites - guda biyu kintinkiri-kamar samuwar, tsakanin wanda aka kafa a cikakke - a sakandare jiki kogo. Yi zurfi a cikin annelids da arthropod.
2. A rudiment na notochord - mãkirci mesodam, wanda a nan gaba tasowa a cikin wani tsirkiya. A rarrabe vertabrate.
3. A vertabrate somites an kafa daga kowane sclerotome, dermatitis da myotome.
4. Splanchnotome - gefen farantin wanda subdivided cikin biyu jinsin yadudduka: an ciki da kuma wani m. Therebetween a vertabrate aka kafa overall.
5. Nephrotomy - guda biyu tsarin a haɗa splanhnostomy.

Bayan nazarin kowane sashe na jam Layer, da masana kimiyya sun iya sanin abin da yake cikin mesodam, da kuma fahimtar abin da aiki shi aikin.

histogenesis

A mesodam bada Yunƙurin zuwa dama iri kyallen takarda.

1. Parenchyma flatworms, wanda ya cika sarari tsakanin jikinsu. Yana kafa daga mesodam.
2. Wasu epithelial kyallen takarda rufe jikinsu a waje. Wadannan sun hada da secretory Kwayoyin, endocrine da exocrine gland shine yake.
3. Mesodam kafa daga sako-sako da fibrous kuma m fibrous connective nama. Ciki har da samuwar collagen da kuma na roba zaruruwa.
4. Maikacin jini kuma kafa daga mesodam.
5. Kashi da guringuntsi nama, su bijiro da batun kafa abubuwa da mesodermal asalin.
6. By misalin tare da kafa abubuwa na jini, mesodam ne ma shiga a cikin samuwar Kwayoyin na rigakafi da tsarin.
7. Kowane irin tsoka nama. Smooth tsokoki an aza a cikin ganuwar mafi gabobin. Striated zaruruwa ne tsarin abubuwa da kwarangwal tsokoki. Kada ka manta game da striated cardiac tsoka nama, wanda Forms zuciya tsoka.

organogenesis

Tsokoki samar da gabobin, saboda haka, ba wuya a tsammani abin da mãsu su na mesodermal asalin. A rarrabuwa ne ba a kan shafukan mesodam:

• dermatomes - form fata dermis (gumi da sebaceous gland ne wani ɓangare na fata).
• sclerotomes kafa daga m ɓangare na musculoskeletal appatara (kwarangwal).
• na myotomes da bi, - da aiki na musculoskeletal tsarin (tsokoki).
• splanhnostomy ba Yunƙurin zuwa mesothelium - guda Layer epithelium cewa Lines da sakandare jiki kogo.
• nephrostomy Kwayoyin samar excretory da kuma haihuwa tsarin.

Provisory gabobin da mesodermal asalin

Yana da daraja a ambaci wadanda gabobin da suke a matakai daban-daban na yanayin halitta na juya an rasa bayan wasan kwaikwayon na ta ayyuka. Suna da ake kira provisionally. Wadannan sun hada da:

1. Amnion - daya daga cikin membranes amfrayo, wanda ya yi aikin da dama da harshen damo. Na farko shi ne ya haifar da wani ruwa yanayi ga ci gaban da tayin. Dalilin shi ne, samuwar jiki ya kamata a gudanar a ruwa. Domin vertabrate zaune a ƙasar, ruwa a cikin wannan hali ne mai iyakance factor, don haka wannan harsashi da aka kafa a cikin shakka daga juyin halitta. Amnion kuma kare 'ya'yan daga lalacewa, tallafawa matsakaici ta rike akai gishiri taro a akai matakin, da kuma hana amfrayo daga kufan guba abubuwa.
2. Allantois - wani tayi jiki wanda ya yi aikin biyu da ayyuka na abinci mai gina jiki da kuma numfasawa. By asalin ne outgrowth na jakar kwai, wanda ke nufin cewa shi ne ma kafa ta sel da indodem, da kuma mesodam. A cikin mutane da allantois ne kasa da suka ci gaba fiye da sauran 'yan vertebrate, amma a kan shi ne jini, wanda sai fada cikin cibiyarki igiyar nama.
3. Da kuma jakar kwai. Wannan wucin gadi jiki yana dauke da zama dole na gina jiki ga ci gaban da tayin. A samuwar jakar kwai mesodam Kwayoyin da shiga, da kuma indodem. An ban sha'awa alama ne da samuwar jiki a shi da farko jini Kwayoyin na jiki.
4. Cibiyarki igiyar (cibiyarki igiyar) - haɗu da amfrayo da kuma mahaifa.
5. Chorion - tayi daina kai hare hare via wanda da aka makala to ya zauna cikin mahaifa, kuma Mahaifa samuwar.
6. Mahaifa yana - kadai sashin jiki a cikin mutum tsokoki kafa biyu kwayoyin: uwar da tayin. tayin ta hanyar mahaifa jini Daga uwar sami gina jiki da kuma oxygen.

ayyuka mesodam

Mun gani, abin da mesodam. Mene ne ayyuka na jam Layer?

Mesodam ci gaban da ya yarda flatworms cika a cikin gibba tsakanin jikin na parenchymal nama. A mafi m kwayoyin parenchyma ba, amma manufa shi ne irin wannan: mesodermal asalin kyallen takarda samar da iyaka yadudduka tsakanin jikinsu. Mezoblasta mafi muhimmanci aiki ne da samuwar wucin gadi gabobin amfrayo (allantois, da cibiyarki igiyar, Mahaifa, da dai sauransu ...) Har ila mesodam Kwayoyin samar da ciki yanayi na nama, jini da kuma Lymph.

ƙarshe

Yanzu za ka iya cikakken bayyana abin da mesodam. Ta ilimi ya yarda dabbobi su matsa zuwa wani sabon mataki na ci gaba, kamar yadda evidenced da asalin yawa gabobin da kyallen takarda. Bugu da ƙari kuma, da samuwar na amniotic membrane sa wani ingantaccen tsalle a gaban vertabrate. Saboda haka, da mesodam ne wani muhimmin juyin kashi.